package com.weixin.util;
import java.io.InputStream;
import java.io.Writer;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.core.util.QuickWriter;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.xml.PrettyPrintWriter;
import com.thoughtworks.xstream.io.xml.XppDriver;
import javax.servlet.http.HttpServletRequest;

import com.weixin.message.impl.Article;
import com.weixin.message.impl.MusicMessage;
import com.weixin.message.impl.NewsMessage;
import com.weixin.message.impl.TextMessage;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
/**
 * Created by Tonight on 2017/3/31.
 */
public class MessageUtil {

    //APPID
    public static final String appID = "wx3d1d23a7073b29d5";
    //appsecret
    public static final String appsecret = "pFZoW6ZPie10EZQgyG3ERkS31LewKKNsoGFSrAvcg8M";

    public static final String RESP_MESSAGE_TYPE_TEXT = "text";
    public static final Object REQ_MESSAGE_TYPE_TEXT = "text";
    public static final Object REQ_MESSAGE_TYPE_IMAGE = "image";
    public static final Object REQ_MESSAGE_TYPE_VOICE = "voice";
    public static final Object REQ_MESSAGE_TYPE_VIDEO = "video";
    public static final Object REQ_MESSAGE_TYPE_LOCATION = "location";
    public static final Object REQ_MESSAGE_TYPE_LINK = "link";
    public static final Object REQ_MESSAGE_TYPE_EVENT = "event";
    public static final Object EVENT_TYPE_SUBSCRIBE = "SUBSCRIBE";
    public static final Object EVENT_TYPE_UNSUBSCRIBE = "UNSUBSCRIBE";
    public static final Object EVENT_TYPE_SCAN = "SCAN";
    public static final Object EVENT_TYPE_LOCATION = "LOCATION";
    public static final Object EVENT_TYPE_CLICK = "CLICK";
    public static String PREFIX_CDATA = "<![CDATA[";
    public static String SUFFIX_CDATA = "]]>";
    /**
     * 扩展xstream，使其支持CDATA块
     * 由于xstream框架本身并不支持CDATA块的生成，下面代码是对xtream做了扩展，
     * 使其支持在生成xml各元素值时添加CDATA块。
     * @date 2013-05-19
     */
    private static XStream xstream = new XStream(new XppDriver() {
        public HierarchicalStreamWriter createWriter(Writer out) {
            return new PrettyPrintWriter(out) {
                // 对所有xml节点的转换都增加CDATA标记
                boolean cdata = true;
                @SuppressWarnings("unchecked")
                public void startNode(String name, Class clazz) {
                    super.startNode(name, clazz);
                }
                protected void writeText(QuickWriter writer, String text) {
                    if (cdata) {
                        writer.write(PREFIX_CDATA);
                        writer.write(text);
                        writer.write(SUFFIX_CDATA);
                    } else {
                        super.writeText(writer, text);
                    }
                }
            };
        }
    });

    /**
     * 解析微信发来的请求(xml)
     *
     * @param request
     * @return
     * @throws Exception
     */
    @SuppressWarnings({ "unchecked", "rawtypes" })
    public static Map parseXml(HttpServletRequest request) throws Exception {
        // 将解析结果存储在HashMap中
        Map map = new HashMap();

        // 从request中取得输入流
        InputStream inputStream = request.getInputStream();
        // 读取输入流
        SAXReader reader = new SAXReader();
        Document document = reader.read(inputStream);
        // 得到xml根元素
        Element root = document.getRootElement();
        // 得到根元素的所有子节点
        List<Element> elementList = root.elements();
        // 遍历所有子节点
        for (Element e : elementList)
            map.put(e.getName(), e.getText());

        // 释放资源
        inputStream.close();
        inputStream = null;
        return map;
    }

    /**
     * 文本消息对象转换成xml
     *
     * @param textMessage
     *            文本消息对象
     * @return xml
     */
    public static String textMessageToXml(TextMessage textMessage) {
        xstream.alias("xml", textMessage.getClass());
        //xstream.processAnnotations(textMessage.getClass());
        System.out.println(xstream.toXML(textMessage));
        return xstream.toXML(textMessage);
    }

    /**
     * 音乐消息对象转换成xml
     *
     * @param musicMessage
     *            音乐消息对象
     * @return xml
     */
    public static String musicMessageToXml(MusicMessage musicMessage) {
        xstream.alias("xml", musicMessage.getClass());
        return xstream.toXML(musicMessage);
    }

    /**
     * 图文消息对象转换成xml
     *
     * @param newsMessage
     *            图文消息对象
     * @return xml
     */
    public static String newsMessageToXml(NewsMessage newsMessage) {
        xstream.alias("xml", newsMessage.getClass());
        xstream.alias("item", new Article().getClass());
        return xstream.toXML(newsMessage);
    }
}
